/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.    
 */
package dk.redillusions.jdbc.proxy.statistics;

/**
 * Class containing the statistics of {@link java.sql.Statement}s and
 * {@link java.sql.PreparedStatement}s. An instance of this class contains
 * statistics for all {@link java.sql.Statement}s and
 * {@link java.sql.PreparedStatement}s used in the period in which it has been
 * running (see {@link #start()} and {@link #stop()}).
 * 
 * @author Sune Wettersteen
 * 
 */
class AggregatedStatementStatistics extends AbstractStatementStatistics implements IAggregatedStatementStatisticsReporter, IStatementStatisticsCollector, IPreparedStatementStatisticsCollector {
    /**
     * Lock.
     */
    private Object lock = new Object();

    /**
     * Whether or not statistics or currently being collected.
     */
    private boolean running = false;

    /**
     * {@inheritDoc}
     */
    @Override
    public void start() {
        synchronized (this.lock) {
            // Check if we are already started
            if (this.running) {
                return;
            }

            final StatisticsService service = StatisticsService.getInstance();
            service.addStatementStatistics(this);
            service.addPreparedStatementStatistics(this);

            this.running = true;
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void stop() {
        synchronized (this.lock) {
            // Check if we have already stopped
            if (!this.running) {
                return;
            }

            final StatisticsService service = StatisticsService.getInstance();
            service.removeStatementStatistics(this);
            service.removePreparedStatementStatistics(this);

            this.running = false;
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean isRunning() {
        return this.running;
    }
}
